1. Field of the Invention
This invention relates to a ratchet wrench, particularly to a ratchet wrench structure.
2. Description of the Prior Art
A conventional ratchet wrench, referring to FIGS. 1 and 2, has one end provided with an accommodating groove 1 received therein with a ratchet wheel 2, which has its circumferential side circularly provided with gear teeth. An actuating member 3 is pivotally received in the accommodating groove 1 and a restraining block 4 is slidably mounted between the ratchet wheel 2 and the actuating member 3. The restraining block 4 has one side adjacent to the ratchet wheel 2 disposed thereon with gear teeth to be engaged with the gear teeth of the ratchet wheel 2 and another side formed with two recessed portions 5. The actuating member 3 is provided with a position-limiting groove 6 corresponding with the recessed portion 5, a push block 7 and an elastic piece 8. The sealing end of the position-limiting groove 6 is connected with the push block 7 via the elastic piece 8 to let the push block 7 actuated to push against the restraining block 4.
Thus, by the force of rotation of the ratchet wheel and via the force exerted by the push block 7, the restraining block 4 will be actuated to push against the elastic member 8 and carry out reciprocating movement by extension and contraction of the elastic piece 8. When the actuating member 3 is turned, the elastic piece 8 will be actuated by the push block 7 to optionally push one of the two recessed portions 5 of the restraining block 4 and have one corresponding sidewall of the restraining block 4 resisting against the inner wall of accommodating groove 1. At this time, the ratchet wheel 2 is limited by the restraining block 4; therefore, the ratchet wheel 2 can be only rotated clockwise or counterclockwise, thus able to attain an effect that the actuating member 3 can be actuated to control the ratchet wheel 2 to carry out unidirectional driving.
However, there is an excessively large disparity in size ratio between the area of the pushing face of the push block 7 and the area of the recessed portion 5, and the location that the push block 7 pushes against the recessed portion 5 is not good; therefore, when the restraining block 4 is stressed by rotation of the ratchet wheel 2, the restraining block 4 is unable to evenly apply force on both the push block 7 and the elastic piece 8, thus resulting in misgivings that the structure of ratchet wrench may stop operating in use and that the ratchet wrench may cause structural damage. In addition, the components of the conventional ratchet wrench is too numerous and hence more molds must be made, thus increasing manufacturing cost and complicating assembly procedure. In view of above-mentioned situation, the inventor of this invention thinks that the structure of the conventional ratchet wrench is necessary to be ameliorated and hence devises this invention.